It doesn’t matter if you’re choosing an Agile development framework like SAFe or an Agile Transformation Framework like the LeadingAgile Basecamp model, the models and frameworks are incomplete, by design. They need to be adapted to meet your organizational goals. Do you think the Agile Manifesto would have lasted as long as it has, if it answered all of your questions in two pages? To that, if you think all of your questions are completely answered by a single “big picture” poster, you’re being naive. But, that’s exactly what I see happening. Realize that you have permission to mix and mash whatever you need, to make your organization operate better. The Agile police are not going to break down your door because you’re not following a framework as it was originally written. If that is what you think, what happens if the author or creator of the framework or model you're following changes it? Does that mean your business is now broken?
Don’t just follow the horde of people that are choosing frameworks because they look pretty on a poster. It's not a car! Look for a framework that looks like a potential organizational end-state. Evaluate what your company values from a planning perspective. Next, evaluate what your customers value from a planning perspective. Pick a framework and then refine it (through structure, governance, and metrics/tools) to align with an ideal end-state.